Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 1,462	$ 1,262	$ 1,610	$ 2,572
Other comprehensive (loss) income:
Unrealized holding (losses) gains on available-for- sale securities, net of tax	(174)	39	(179)	44
Foreign currency translation adjustments	(768)	(779)	273	(1,318)
Other comprehensive (loss) income	(942)	(740)	94	(1,274)
Comprehensive (loss) income	$ 520	$ 522	$ 1,704	$ 1,298

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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